Dumfries was born in Dungannon, Northern Ireland and grew up playing football with his local team, Dungannon Swifts. He began his professional career at the age of 18 when he signed for Scottish club Dunfermline Athletic.

In 2007, Dumfries moved to Italy and joined Serie A side Inter Milan on loan from Dunfermline. He made his debut for Inter in February 2007 against Bari and went on to make 45 appearances for the club during his loan spell.

After returning to Dunfermline, Dumfries continued to impress and was eventually sold to Italian giants Juventus in January 2009. In his first season at Juventus, Dumfries made 36 appearances and scored two goals as the club won the Coppa Italia.

However, Dumfries struggled to break into the Juventus squad and was eventually released by the club in June 2011. Despite this setback, Dumfries remained a highly talented player and went on to play for various other clubs including Celtic, Rangers, and St Mirren.

Despite his impressive career, Dumfries has never managed to win any major trophies with any of his former clubs or with Italy's national team. However, his contributions to the game have been significant and he remains a respected figure in the world of football.